Workpiece positioning apparatus

Abstract

Disclosed is an X-Y table for positioning semiconductor workpieces in a vacuum environment with a high degree of speed and accuracy. The X and Y prime movers are mounted on adjacent external surfaces of the vacuum chamber. The first motor associated with the drive in the Y direction seals with an O-ring onto the front surface of the chamber. A second motor associated with the X drive is fixedly mounted to one of the sides of the chamber. The lower stage providing motion in the Y direction has a single degree of freedom relative to the vacuum chamber. The upper stage providing motion in the X direction is connected to the lower Y stage and has two degrees of freedom relative to the vacuum chamber. The entire X-Y table assembly is mounted on rails in parallel with the Y direction of motion such that by removing the front wall of the vacuum chamber, the entire assembly may be removed for repair and/or maintenance. By such modular replacement, the entire E-beam tool can resume operation.

What is claimed is: 
     
       1. A workpiece support apparatus comprising: a remotely positionable workpiece support means adapted for linear motion in each of at least two orthogonal directions contained in an enclosed chamber;   a pair of motive means mounted on the walls externally of the enclosed chamber;   one of the walls of the chamber, having one of the motive means fixedly attached thereto;   said one of the walls and motive means being removable together with at least a portion of the workpiece support means from the enclosed chamber;   each said motive means having respective drive means including a drive shaft passing through an environmental seal and a linear actuator;   said first drive means associated with a first linear actuator having a drive arm attached in fixed relation thereto with a pair of bearings mounted on said drive arm and disposed on either side of a drive rail that is fixedly mounted on a portion of said work piece support means;   such that said drive rail is adapted to slide out from between said bearings.   
     
     
       2. In manufacturing apparatus wherein a workpiece is mounted on an X-Y positionable work station adjacent a permanent tool for manufacturing in a critical environment, the improvement comprising: an environmental housing having a plurality of vertical sides and having the manufacturing tool mounted adjacent thereto;   a work station adapted to linear motion in each of at least two orthogonal directions;   a first prime mover mounted on a first one of said plurality of vertical sides;   a second prime mover mounted on a second one of said plurality of vertical sides;   each said prime movers having respective drive means including a drive shaft passing through an environmental seal and a linear actuator;   said work station and said second prime mover being integrally connected to said second vertical side;   engaging means fixedly attached to the drive means associated with said first prime mover and to said work station;   said engaging means permitting relatively frictionless motion along a longitudinal axis while constraining motion perpendicular to the longitudinal axis;   such that when said second vertical side is disengaged from said environmental housing, at least a portion of said work station and second prime mover are removable together with said second vertical side.   
     
     
       3. In manufacturing apparatus wherein a workpiece is mounted on an X-Y positionable work station adjacent a permanent tool for manufacturing in a critical environment, the improvement comprising: an environmental housing having a plurality of vertical sides and having the manufacturing tool mounted adjacent thereto;   a work station adapted to linear motion in each of at least two orthogonal directions;   a first prime mover mounted on a first one of said plurality of vertical sides;   a second prime mover mounted on a second one of said plurality of vertical sides;   each said prime movers having respective drive means including a drive shaft passing through an environmental seal and a linear actuator;   said work station and said second prime mover being integrally connected to said second vertical side;   such that when said second vertical side is disengaged from said environmental housing, said work station and second prime mover are removable together with said second vertical side;   said first drive means associated with a first linear actuator having a drive arm attached in fixed relation thereto with a pair of bearings mounted on said drive arm and disposed on either side of a drive rail that is fixedly mounted on a portion of said work station;   such that said drive rail is adapted to slide out from between said bearings.   
     
     
       4. An apparatus for manufacturing comprising: an electron beam column;   an environmental housing having a plurality of vertical sides, mounted beneath said electron beam column;   a work station adapted to linear motion in each of at least two orthogonal directions;   a first prime mover mounted on a first one of said plurality of vertical sides;   a second prime mover mounted on a second one of said plurality of vertical sides;   each said prime movers having respective drive means including a drive shaft passing through an environmental seal and a linear actuator;   said work station and said second prime mover being integrally connected to said second vertical side;   such that when said second vertical side is disengaged from said environmental housing, said work station and second prime mover are removable together with said second vertical side;   said first drive means associated with a first linear actuator having a drive arm attached in fixed relation thereto with a pair of bearings mounted on said drive arm and disposed on either side of a drive rail that is fixedly mounted on a portion of said work station;   such that said drive rail is adapted to slide out from between said bearings.   
     
     
       5. A workpiece support apparatus comprising: a remotely positionable workpiece support means adapted for linear motion in each of at least two orthogonal directions contained in an enclosed chamber;   first and second motive means mounted on the walls externally of the enclosed chambers;   one of the walls of the chamber, having the first motive means fixedly attached thereto;   said one of the walls and first motive means being removable together with at least a portion of the workpiece support apparatus from the enclosed chamber;   each said first and second motive means having respective first and second drive means;   engaging means fixedly attached to the second drive means and to said workpiece support apparatus;   said engaging means permitting relatively frictionless motion along a longitudinal axis while constraining motion perpendicular to the longitudinal axis;   such that at least a portion of said workpiece support apparatus is adapted to be disengaged from said second drive means.